Self cancelling direction indicator switches

ABSTRACT

A self-cancelling direction indicator switch for a road vehicle comprising a body for attachment to a vehicle. An operating member is movable with respect to the body to complete the indicator lamp circuits in respective positions of the operating member relative to the body, and there is provided cancelling means for returning the operating member to a neutral position. The cancelling means is carried by the body and includes first and second annular members secured together, and defining an external groove by means of which the annular members are held captive on an inwardly projecting portion of the body. The first annular member includes an inwardly directed key for engagement in a slot in the steering shaft, and a projection on the first annular member effects return of the operating member to its neutral position when the steering shaft is rotated relative to the body.

United States Patent [191 Cryer Dec. 18, 1973 [5 1 SELF CANCELLINGDIRECTION 3,300,601 1/1967 Du Rocher et a1. ZOO/61.34 INDICATOR SWITCHESI 3,431,373 3/1969 Fuqua ZOO/61.34

75 l t 1 EdwadCre,l-lih ,N. l 1 men or Bumlzy g g g am r PrimaryExaminer-J. R. Scott A!t0rney.lohn C. Holman et a1. [7311 Assignee:Joseph Lucas (Industries) Limited,

B'rm'n ha E 1 d 2 l l g m an 57 ABSTRACT 2 F' ed: A r. 24 1972 l 1 l p Aself-cancelling direction indicator switch for a road pP 246,534 vehiclecomprising a body for attachment to a vehicle. An operating member ismovable with respect to the [30] Foreign Application Priority Data bodyt0 complete the indicator lamp circuits n re- 29 97 I B spectlvepositions of the operating member relative to l 1 Great 2248/71 thebody, and there is provided cancelling means for returning the operatingmember to a neutral position. [52] US. Cl ZOO/61.27,ZOO/61.122000966113554, The cancelling means is carried by the body andInt "01h 2 cludes first and second annular members secured together anddefining an external groove by means of [58] Field of Search200/61.27-61.35, 61.54 which the annular members are held captive on an'wardly projecting portion of the body. The first annular memberincludes an inwardly directed key for en- [56] References cued gagementin a slot in the steering shaft, and a projec- UNITED STATES PATENTStion on the first annular member effects return of the 2,757,250 7/1956Brown et a1. ZOO/61.34 operating member to its neutral position when the3 3 Li ln t a1 200/6135 X steering shaft is rotated relative to thebody. 2,800,541 7/1957 Brown et al. ZOO/61.34 2,800,542 7/1957 Barcus etal ZOO/61.34 2 Claims, 3 Drawing Figures I ll 2O 18 g N O 19 I h 2 24o--- \Fa' J U J L I I0 27 I I u 12 20 u 7 PAIENIED 3.780.241

' sum 2 Hi2 SELF CANCELLING DIRECTION INDICATOR SWITCHES This inventionrelates to self-cancelling direction indicator switches for roadvehicles.

According to the invention a direction indicator switch comprises a bodyforattachment to a vehicle, an operating number movable with respect tothe body for completing in use circuits to the indicator lamps, andcancelling means for returning the operating member to a neutralposition, the cancelling means being carried by the body and including afirst annular member having at least one inwardlydirected finger forengagement in a slot in the steering shaft of the vehicle, a projectionon the first annular member for effecting return of the operating memberto its neutral position on turning of the steering shaft relative to thebody and a second annular member secured to the first annular member,said first and second annular members defining an external groove bymeans of which the annular members are held captive on an inwardlyprojecting portion of the body.

An example of the invention is shown in the accompanying drawings inwhich:

FIG. 1 is a section through the switch,

FIG. 2 is a fragmentary view showing a portion of the cancelling meansof the switch, and

FIG. 3 is a fragmentary view taken on line 33 in FIG. 1.

The switch includes a body with lugs 11 whereby it can be mounted on asupport surrounding the steering shaft of a vehicle. The body has apassage 12 through which the steering shaft extends. A fixed contactcarrier 13 which also has a passage 14, aligned with the passage 12, issecured to the body 10. As may be seen from FIG. 3 this carrier 13 has acam face 15 comprising a central V-shaped notch and a pair of smallerV-shaped notches on opposite sides of the central notch respectively.

Pivotally mounted on the body 10 by means of a pivot pin 16,diametrically" opposite the central notch of the cam face, is anoperating member 17 on which there is mounted a movable contact carrier18. A roller 19 is slidable in a passageway defined between the carrier18 and the member 17 and is spring loaded into engagement with the camface 15. The roller 19 and the cam face 15 co-act to locate the member17 in three alternative positions, namely a neutral position in whichthe plunger engages in the central notch and two actuated positions inwhich the plunger 19 engages in the two smaller notches. It will beappreciated that only a small displacement ofthe operating member fromits actuated positions is required to engage the plunger with one flankof the central notch so that the member 17 is returned to its neutralposition.

The two contact carriers have contacts 20, 21 thereon such that onecircuit is completed when the member 17 is in one actuated position andanother is completed when it is in its other actuated position in knownmanner.

For providing the self-cancelling feature of the switch, a pair of pawls22, 23 are pivotally mounted on the member 17 and are urged towards oneanother by a tension spring 24. The pawl 22 is movable in a clockwisedirection about a pivot axis, but cannot be moved from the positionshown in the other direction. Similarly the pawl 23 can be turned on inan anti-clockwise direction.

To co-act with the pawls 22, 23 there is provided a projecting peg 25which is secured to a first sheet metal, annular member 26 which isdisposed in the passage 12. The annular member 26 has two inwardlydirected fingers 26a which engage in longitudinal slots in the steeringshaft so as to cause the member 26 to rotate with the steering shaft. Ahole 40 is formed in the member 26 adjacent at least one of the fingers26a, this location being selected in that the additional width of theannular member 26 created by each of the inwardly directed fingers 26aensures that the member 26 is not excessively weakened by a holetherein. The peg 25 extends through one of the holes as shown.

Secured to the member 26 is a second annular member 27 formed of asynthetic resin material. The member 27 is shaped at its outer peripheryto form, in combination with the member 26, an external groove in whichan integral annular rib in the passage 12 is held captive. The twoannular members 26, 27 are assembled in situ in the passage 12. Theassembly is rotatable relative to the body.

In use it will be appreciated that the peg 25 moves with the steeringshaft relative to the body. When the member 17 is in its neutralposition neither of the pawls 22, 23 is in the path of the peg. When themember 17 is manually displaced to one of its actuated positions, forexample in a clockwise direction as viewed in FIG. 3, the pawl 23 isbrought into the path of the peg 25. When the steering shaft is turnedin a clockwise direction, the peg 25 strikes the pawl 23 and causes thepawl 23 to be turned in an anti-clockwise direction, however, the pawlcan be displaced relative to the member 17 when it is struck by the peg25 and the member 17 is moved in an anti-clockwise direction. The member17 is returned to its neutral position by the action of the springloaded plunger 19. v

In a modification the peg 25 is welded to the member 26 rather thanbeing carried in a hole in the member 26. Moreover, the steering shaftcan include a clip defining said longitudinal slot or slots the clipbeing nonrotatably mounted on the shaft to ensure a driving connectionbetween the member 26 and the shaft through the clip and the fingers26a.

We claim:

l. A self-cancelling direction indicator switch for a road vehicle,comprising a body for attachment to a vehicle, an operating membermovable with respect to the body for completing in use circuits to theindicator lamps, and cancelling means for returning the operating memberto a neutral position, said cancelling means being carried by said bodyand including a first annular member having at least one inwardlydirected finger for engagement in a slot in the steering shaft of thevehicle, a projection on said first annular member for effecting returnof said operating member to its neutral position on turning of saidsteering shaft relative to said body and a second annular member securedto said first an nular member, said first and second annular membersdefining an external groove by means of which said annular members areheld captive on an inwardly projecting portion of said body.

2. A self-cancelling direction indicator switch as claimed in claim 1wherein said projection is provided on said first annular memberadjacent said inwardly directed finger.

1. A self-cancelling direction indicator switch for a road vehicle,comprising a body for attachment to a vehicle, an operating membermovable with respect to the body for completing in use circuits to theindicator lamps, and cancelling means for returning the operating memberto a neutral position, said cancelling means being carried by said bodyand including a first annular member having at least one inwardlydirected finger for engagement in a slot in the steering shaft of thevehicle, a projection on said first annular member for effecting returnof said operating member to its neutral position on turning of saidsteering shaft relative to said body and a second annular member securedto said first annular member, said first and second annular membersdefining an external groove by means of which said annular members areheld captive on an inwardly projecting portion of said body.
 2. Aself-cancelling directiOn indicator switch as claimed in claim 1 whereinsaid projection is provided on said first annular member adjacent saidinwardly directed finger.